The best goldfish food

Fancy goldfish — orandas, ryukins, fantails, lionheads — have compressed bodies that push the swim bladder and gut into an unnatural arrangement. Gulping air at the surface makes that worse, and the result is the fish that floats at an angle or sits on the bottom after meals.

A sinking pellet removes the gulping entirely. The fish takes food in mid-water or off the substrate with its head down, which is how a goldfish is built to feed.

The honest costs. 6 mm is genuinely big: check your fish's mouth and buy the medium or small pellet for anything not yet adult. Sinking food is also harder to see, so uneaten pellets hide in the gravel and rot — measure what you drop in. Omega One's own site fails TLS verification from here, so no guaranteed analysis is printed.

The round-bodied fancy varieties are the ones most prone to buoyancy trouble, and this food is formulated and sized for them: small, sinking, and intended as a daily staple rather than a treat.

Mini pellets are also easier to portion. A dozen small pellets is a visible amount of food in a way that three large ones is not, which makes overfeeding slightly harder.

The honest costs. It is the most expensive food here and the pot is large for one or two fish, so decant and store the rest sealed. Hikari's site does not respond to us, so no guaranteed analysis is printed. And a sinking pellet in a bare-bottom tank is easy to see, while in deep gravel it disappears — vacuum accordingly.

Common and comet goldfish — the single-tailed, torpedo-shaped ones — do not have the body-shape problem the fancies have, and a floating flake is much less of a risk for them.

The added algae matters for both types. A goldfish digestive system expects a steady supply of plant matter, and a diet of protein pellets alone contributes to the constipation that gets misdiagnosed as swim-bladder disease.

The honest costs. It floats, so for a fancy goldfish it carries the gulping risk unless you soak it first. Added algae is a component of a vegetable diet, not the whole thing — a blanched pea or a slice of zucchini does more for a constipated goldfish than any flake. Tetra's site does not respond to us, so no guaranteed analysis is printed.

Most beginners reading this already own an API test kit, and there is something to be said for a food from a brand whose products you can find in any shop when you run out.

As a staple it is competent and mid-priced, and the pot size suits a one or two fish tank better than the large bags aimed at pond keepers.

The honest costs. API's own site does not publish a guaranteed analysis we could load, so none is printed here. It is sold as a general goldfish food, so if you keep a round-bodied fancy with a history of floating, a dedicated sinking pellet is the better choice.

This is the skip entry and it needs care, because it is not a bad food — it is the wrong format for the fish most people keep.

Flakes float. A fancy goldfish attacking floating food takes in air with every mouthful, and air in a compressed-bodied fish is what produces the tilting, floating and sinking that owners describe as swim-bladder disease. The fish is usually not diseased; it is full of air and constipated.

For a single-tailed common or comet goldfish in a pond or a large tank, flakes are fine. For a fancy in an aquarium, either buy a sinking pellet or soak the flakes in tank water for thirty seconds before feeding so they sink.

Cheap is a genuine virtue and this is the cheapest food here per ounce. It is on this page so you can make that trade knowingly rather than by default.